Sure, 1 rooster could guard 34 hens if he happens to be in the right place at the right time, but this isn't always the case. 1 rooster for every 15-20 hens is best, and your flock could probably use another.

That said, how a rooster guards is flock has a lot to do with their breeding and temperament, so choose wisely.

My history with roosters is that 1 is good, 2 are enemies, and 3 or more learn to get along. In other words, the testoserone between 2 is usually lethal to one. But a whole bunch seem to work out a system of getting along.

According to me you should keep them.